Methods and apparatus for manufacturing fiber-based beverage holders

ABSTRACT

Methods and apparatus for vacuum forming a beverage carrier yoke using a slurry. The slurry comprises: a moisture barrier comprising AKD in the range of about 4% by weight; and a fiber base comprising OCC and NP.

TECHNICAL FIELD

The present invention relates, generally, to ecologically sustainablemethods and apparatus for manufacturing beverage yokes and, moreparticularly, to the use of novel yoke designs and slurry compositionsfor use in vacuum forming molded fiber beverage carriers.

BACKGROUND

Pollution caused by single use plastic containers and beverage carriersis epidemic, scarring the global landscape and threatening the health ofecosystems and the various life forms that inhabit them. Six pack rings,or yokes, typically comprise a web of interconnected plastic rings usedto carry multi-packs of cans or bottles. Since 1989, six-pack rings inthe United States have been formulated to be photo-degradable, so thatthe plastic begins to disintegrate within a few weeks. More recently,the yokes are made from #4 Plastic, or LDPE photodegradable plastic(polyethylene). While these new materials reduce the environmentalimpact of beverage yokes, there remains a need for a more biocompatiblesolution.

Sustainable solutions for reducing plastic pollution continue to gainmomentum. However, adoption requires these solutions to not only be goodfor the environment, but also competitive with plastics from both aperformance and a cost standpoint. The present invention involvesreplacing plastic beverage yokes with revolutionary technologies inmolded fiber without compromising product performance, within acompetitive cost structure.

By way of brief background, molded paper pulp (molded fiber) has beenused since the 1930s to make containers, trays and other packages, butexperienced a decline in the 1970s after the introduction of plasticfoam packaging. Paper pulp can be produced from old newsprint,corrugated boxes and other plant fibers. Today, molded pulp packaging iswidely used for electronics, household goods, automotive parts andmedical products, and as an edge/corner protector or pallet tray forshipping electronic and other fragile components. Molds are made bymachining a metal tool in the shape of a mirror image of the finishedfiber based product. Holes are drilled through the tool and then ascreen is attached to its surface. A vacuum is drawn through the holeswhile the screen prevents the pulp from clogging the holes. The pulpparticulates accumulate at the screen surface to form the molded part.

Fiber-based packaging products are biodegradable, compostable and,unlike plastics, do not migrate into the ocean. However, presently knownfiber technologies are not well suited for beverage yokes due to thehigh stress concentrations surrounding the carrying holes, as well asthe tendency of fiber based products to quickly degrade when wet.

Methods and apparatus are thus needed which overcome the limitations ofthe prior art.

Various features and characteristics will also become apparent from thesubsequent detailed description and the appended claims, taken inconjunction with the accompanying drawings and this background section.

BRIEF SUMMARY

Various embodiments of the present invention relate to methods, chemicalformulae, and apparatus for manufacturing vacuum molded, fiber-basedbeverage carrier yokes including, inter alia: i) slurry compositionswhich promote strength and structural rigidity in the finished fiberyoke; ii) slurry compositions which resists moisture penetration in thefinished fiber yoke; iii) vacuum tooling configured to yield sharp edgessurrounding the beverage can holes without the need for subsequent diecutting; iv) geometric designs which minimize weight to thereby reducecycle time and increase throughput; v) geometric designs which securelyretain the beverage containers while also promoting easy removal of eachbeverage container from the yoke; and vi) a fiber based slurrycomposition including in the range of 4% kymene 1500LV, 4% AKD, and 4%Hercobond 6950.

It should be noted that the various inventions described herein, whileillustrated in the context of conventional slurry-based vacuum formprocesses, are not so limited. Those skilled in the art will appreciatethat the inventions described herein may contemplate any fiber-basedmanufacturing modality, including 3D printing techniques.

Various other embodiments, aspects, and features are described ingreater detail below.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

Exemplary embodiments will hereinafter be described in conjunction withthe appended drawing figures, wherein like numerals denote likeelements, and:

FIG. 1 is a perspective view of a fiber based beverage yoke carrying sixbeverage cans in accordance with various embodiments;

FIG. 2 is a schematic diagram of a beverage can illustrating the shapeof the top of the can to which a beverage yoke is secured in accordancewith various embodiments;

FIG. 3 is a perspective view of an exemplary fiber based six packbeverage yoke in accordance with various embodiments;

FIG. 4 depicts respective top plan, side, and front elevation views ofthe yoke shown in FIG. 3 in accordance with various embodiments;

FIG. 5 depicts respective top plan, side, and front elevation views ofan alternate yoke embodiment in accordance with various embodiments;

FIG. 6 a perspective view of a fiber based four pack beverage yoke inaccordance with various embodiments;

FIG. 7 depicts respective top plan, side, and front elevation views ofthe yoke shown in FIG. 6 in accordance with various embodiments;

FIG. 8 is a perspective view of an exemplary male die componentconfigured for use in vacuum forming a fiber based beverage yoke inaccordance with various embodiments;

FIG. 9 is a perspective view of an exemplary male drying press componentfor drying a fiber based beverage yoke in accordance with variousembodiments;

FIG. 10 is a perspective view of an exemplary female drying presscomponent in accordance with various embodiments;

FIG. 11 is a schematic block diagram of an exemplary vacuum formingprocess using a fiber-based slurry in accordance with variousembodiments; and

FIG. 12 is a schematic block diagram of an exemplary closed loop slurrysystem for controlling the chemical composition of the slurry inaccordance with various embodiments.

DETAILED DESCRIPTION OF PREFERRED EXEMPLARY EMBODIMENTS

The following detailed description of the invention is merely exemplaryin nature and is not intended to limit the invention or the applicationand uses of the invention. Furthermore, there is no intention to bebound by any theory presented in the preceding background or thefollowing detailed description.

Various embodiments of the present invention relate to fiber-based orpulp-base ring yokes for use in carrying bottles, cans, and othercontainers for both consumables and non-consumables. By way ofnon-limiting example, the present disclosure relates to particulargeometries and chemical formulations of slurries adapted to address theunique challenges associated with beverage carrier yokes. The presentdisclosure further contemplates fiber-based yokes having structuralfeatures for enhanced strength.

Vacuum formed food carriers are well known, including trays equippedwith press fit cup holders for supporting beverage containers on top ofthe carrier. However, presently known fiber based food carriers are notwell suited for use as “six pack” rings or yokes for suspending beveragecontainers below the plane of the yoke, in part due to the challengesassociated with gripping the containers with sufficient strength toretain them in the yoke, while at the same time facilitating easyremoval of the containers form the yoke. That is, if the yoke materialis too thick, it may be difficult to dislodge a can from the yoke. Ifthe material is too thin, the yoke may not adequately retain thebeverage containers as the yoke is carried by a user.

Various embodiments contemplate a carrying yoke having a substantiallyuniform thickness; other embodiments contemplate a greater thickness inhigh stress concentration regions, such as proximate the finger holesand the collars for carrying the beverage containers. In otherembodiments ribs and/or other geometric structures may be used toenhance strength.

Other embodiments contemplate infusing the pulp slurry with a wetstrength additive (e.g., Kymene), a dry strength component (e.g.,Topcat® cationic additive), and/or moisture barriers (e.g., 3% AKD).

Other embodiments contemplate perforations or tear lines disposedproximate the container collars to facilitate removal of the containersfrom the yoke.

The present invention further contemplates fiber compositions comprisingin the range of 90% old corrugated containers (OCC) and in the range of10% softwood; other embodiments comprise a slurry base of approximately30% newsprint (NP) and approximately 70% OCC.

Other embodiments contemplate a yoke having a total weight in the rangeof 4-15 grams; particular embodiments target 6.5 or 10 grams. For agiven material, the resulting strength is proportional to thicknesswhich is proportional to weight. One design metric involves optimizingstrength, without unnecessarily increasing thickness, as increasingthickness also increases cycle time and decreases throughput.

Various embodiments contemplate dwell times in the vacuum chamber in therange of 20 seconds, and drying times in the range of 4o seconds @ 200°C., where drying time is also proportional to yoke thickness/weight.

To avoid unnecessary die cutting operations, various embodimentscontemplate aluminum male and female die forms, augmented with toolsteal for those die portions which define the inside ring that holdseach can; in this way very tight tolerances may be maintained, yieldingclean internal edges of the can holders.

With momentary reference to FIGS. 11 and 12, an overview of exemplaryvacuum forming processes useful in the context of the present inventionwill now be presented.

FIG. 11 depicts an exemplary vacuum forming system and process 1100using a fiber-based slurry includes a first stage 1101 in which mold(not shown for clarity) in the form of a mirror image of the product tobe manufactured is envelop in a thin wire mesh form 1102 to match thecontour of the mold. A supply 1104 of a fiber-based slurry 1104 is inputat a pressure (P1) 1106 (typically ambient pressure). By maintaining alower pressure (P2) 1108 inside the mold, the slurry is drawn throughthe mesh form, trapping fiber particles in the shape of the mold, whileevacuating excess slurry 1110 for recirculation back into the system.

With continued reference to FIG. 11, a second stage 1103 involvesaccumulating a fiber layer 1130 around the wire mesh in the shape of themold. When the layer 1130 reaches a desired thickness, the mold enters athird stage 1105 for either wet or dry curing. In a wet curing process,the formed part is transferred to a heated press (not shown) and thelayer 1130 is compressed and dried to a desired thickness, therebyyielding a smooth external surface finish for the finished part. In adry curing process, heated air may be passed directly over the layer1130 to remove moisture therefrom, resulting in a more textured finishmuch like a conventional egg carton.

In accordance with various embodiments the vacuum mold process isoperated as a closed loop system, in that the unused slurry isre-circulated back into the bath where the product is formed. As such,some of the chemical additives (discussed in more detail below) areabsorbed into the individual fibers, and some of the additive remains inthe water-based solution. During vacuum formation, only the fibers(which have absorbed some of the additives) are trapped into the form,while the remaining additives are re-circulated back into the tank.Consequently, only the additives captured in the formed part must bereplenished, as the remaining additives are re-circulated with theslurry in solution. As described below, the system maintains a steadystate chemistry within the vacuum tank at predetermined volumetricratios of the constituent components comprising the slurry.

FIG. 12 is a closed loop slurry system 1200 for controlling the chemicalcomposition of the slurry. In the illustrated embodiment a tank 1202 isfilled with a fiber-based slurry 1204 having a particular desiredchemistry, whereupon a vacuum mold 1206 is immersed into the slurry bathto form a molded part. After the molded part is formed to a desiredthickness, the mold 1206 is removed for subsequent processing 1208(e.g., forming, heating, drying, top coating, and the like).

With continued reference to FIG. 12, a fiber-based slurry comprisingpulp and water is input into the tank 1202 at a slurry input 1210. Oneor more additional components or chemical additives may be supplied atrespective inputs 1212-1214. The slurry may be re-circulated using aclosed loop conduit 1218, adding additional pulp and/or water as needed.To maintain a steady state balance of the desired chemical additives, asampling module 1216 is configured to measure or otherwise monitor theconstituent components of the slurry, and dynamically or periodicallyadjust the respective additive levels by controlling respective inputs1212-1214. Typically the slurry concentration is around 0.1-1%. In oneembodiment, the various chemical constituents are maintained at apredetermined desired percent by volume; alternatively, the chemistrymay be maintained based on percent by weight or any other desiredcontrol modality.

The chemical formulae (sometimes referred to herein as “chemistries”)and geometric configurations for various fiber-based beverage carriers,as well as their methods for manufacture, will now be described inconjunction with FIGS. 1-10.

FIG. 1 illustrates a fiber based beverage yoke assembly 100 including asix pack ring palette 104 configured to securely carry a plurality ofbeverage cans 102.

FIG. 2 depicts a typical beverage can 200 having a body 202, a cap 204,a neck 206, and a shoulder 208 extending between the neck and the body.As shown, the diameter 212 of the neck is slightly smaller than thediameter 210 of the cap. Consequently, the yoke collar within which eachcan is secured should advantageously exhibit a diameter which is equalto or slightly greater than dimension 212, while being equal to orslightly less than dimension 212. In addition, the yoke material may bepliable enough to resiliently deform slightly without tearing. In thisway, the collar may slip over the cap 204 when a can is inserted intothe yoke, and thereafter snuggly retain the can about shoulder 208 andor neck 206. As discussed below, the slurry composition and finishedyoke thickness may be configured to yield a yoke of sufficient strengthto securely retain cans, while at the same time allow easy removal ofthe cans from the yoke, as desired.

FIG. 3 depicts an exemplary fiber based six pack beverage yoke 300including a plurality of collars 302 interconnected by a web 304 havingone or more finger holes 306 to facilitate carrying.

FIG. 4 depicts an exemplary yoke 400 having a plurality of collars 402.The yoke 400 is characterized by a collar inside diameter 404 in therange of 1.95 inches (49.408 mm), a center-to-center dimension 406 inthe range of 2.6 inches (66.091 mm), a width dimension 408 in the rangeof 5.26 inches (133.72 mm), a length dimension 403 in the range of 7.87inches (199.817 mm), a height dimension 412 in the range of 0.66 inches(16.700 mm), and a thickness dimension 414 in the range of 0.01 to 0.05inches and preferably about 0.03 inches (0.8 mm).

FIG. 5 depicts an exemplary skinny can yoke 500 having a plurality ofcollars 502. The yoke 500 is characterized by a collar inside diameter504 in the range of 1.91 inches (48.408 mm), a center-to-centerdimension 506 in the range of 2.48 inches (63.09 mm), a width dimension508 in the range of 5.16 inches (131.0 mm), a length dimension 503 inthe range of 7.64 inches (194.1 mm), a height dimension 512 in the rangeof 0.66 inches (16.7 mm), and a thickness dimension 414 in the range of0.01 to 0.05 inches and preferably about 0.03 inches (0.8 mm).

FIG. 6 depicts a four pack beverage yoke 600 including plurality ofcollars 602 and a single finger hole 604.

FIG. 7 depicts an exemplary four can yoke 700 having respective collars702. The yoke 700 is characterized by a collar inside diameter 703 inthe range of 1.91 inches (48.408 mm), respective center-to-centerdimension 704 and 706 in the range of 2.6 inches (66.09 mm), a widthdimension 708 in the range of 5.28 inches (134.0 mm), a length dimension710 in the range of 5.28 inches (134.0 mm), a height dimension 714 inthe range of 0.66 inches (16.7 mm), and a thickness dimension 715 in therange of 0.01 to 0.05 inches and preferably about 0.03 inches (0.8 mm).

FIG. 8 depicts an exemplary male vacuum form die component 802 includinga plurality of collar plugs 804, a wire mesh 806 configured to collectfiber particles into the shape of the finished yoke, and respectivefinger hole plugs 808.

FIG. 9 depicts an exemplary male drying press component 900 includingrespective collar plugs 902 against which the finished yoke 904 ispressed during the drying cycle for drying a fiber based beverage yokein accordance with various embodiments;

FIG. 10 depicts an exemplary female drying press component 1000including female receptors 1004 for securing the finished yoke againstthe corresponding male plugs shown in FIG. 9, and a plurality of ventholes 1006.

Those skilled in the art will appreciate that the tolerances associatedwith the inner diameter of receptors 1004 (FIG. 10) and the outerdiameter of plugs 804 (FIG. 8) may be tightly controlled to achieve aclean cut in the inside diameters of the resulting collars, therebyeliminating the need for subsequent die cutting.

As briefly mentioned above, the various slurries used to vacuum moldcarrying yokes according to the present invention comprises a fiber basemixture of pulp and water, with added chemical components to impartdesired performance characteristics of the finished yoke. The base fibermay include any one or combination of at least the following materials:softwood (SW), bagasse, bamboo, old corrugated containers (OCC), andnewsprint (NP). Alternatively, the base fiber may be selected inaccordance with the following resources, the entire contents of whichare hereby incorporated by this reference: “Lignocellulosic Fibers andWood Handbook: Renewable Materials for Today's Environment,” edited byMohamed Naceur Belgacem and Antonio Pizzi (Copyright 2016 by ScrivenerPublishing, LLC) and available atbooks.google.com/books?id=jTL8CwAAQBAJ&printsec=frontcover#v=onepage&q&f=false; “Efficient Use of Flourescent Whitening Agents andShading Colorants in the Production of White Paper and Board” by LiisaOhlsson and Robert Federe, Published Oct. 8, 2002 in the African Pulpand Paper Week and available attappsa.co.za/archieve/APPW2002/Title/Efficient use of fluorescentw/efficient use of fluorescent w.html; Cellulosic Pulps, Fibres andMaterials: Cellucon '98 Proceedings, edited by J F Kennedy, G OPhillips, P A Williams, copyright 200 by Woodhead Publishing Ltd. andavailable atbooks.google.com/books?id=xO2iAgAAQBAJ&printsec=frontcover#v=onepage&q&f=false; and U.S. Pat. No. 5,169,497 entitled “Application ofEnzymes and Flocculants for Enhancing the Freeness of Paper Making Pulp”issued Dec. 8, 1992.

For vacuum molded produce containers manufactured using either a wet ordry press, a fiber base of OCC and NP may be used, where the OCCcomponent is between 50%-100%, and preferably about 70% OCC and 30% NP,with an added moisture/water repellant in the range of 1%-10% by weight,and preferably about 1.5%-4%, and most preferably about 4%. In apreferred embodiment, the moisture/water barrier component may comprisealkylketene dimer (AKD) (for example, AKD 80) and/or long chaindiketenes, available from FOBCHEM atfobchem.com/html_products/Alkyl-Ketene-Dimer%EF%88AKD-WAX%EF%BC%89.html#.VozozvkrKUk;and Yanzhou Tiancheng Chemical Co., Ltd. atyztianchengchem.com/en/index.php?m=content&c=index&a=show&catid=38&id=124&gclid=CPbn65aUg80CFRCOaQodoJUGRg.

In order to yield specific colors for fiber molded yokes, cationic dyeor fiber reactive dye may be added to the pulp. Fiber reactive dyes,such as Procion MX, bond with the fiber at a molecular level, becomingchemically part of the fabric. Also, adding salt, soda ash and/orincrease pulp temperature will help the absorbed dye to be furtherlylocked in the fabric to prevent color bleeding and enhance the colordepth.

To enhance structural rigidity, a starch component may be added to theslurry, for example, liquid starches available commercially as Topcat®L98 cationic additive, Hercobond, and Topcat® L95 cationic additive(available from Penford Products Co. of Cedar Rapids, IA).Alternatively, the liquid starch can also be combined with low chargeliquid cationic starches such as those available as Penbond® cationicadditive and PAF 9137 BR cationic additive (also available from PenfordProducts Co., Cedar Rapids, IA).

Alternatively or in addition to the foregoing, Topcat L₉₅ may be addedas a percent by weight in the range of 0.5%-10%, and preferably about1%-7%, and particularly for products which need maintain strength in ahigh moisture environment most preferably about 6.5%; otherwise, mostpreferably about 1.5-2.0%.

Dry strength additives such as Topcat L95 or Hercobond which are madefrom modified polyamines that form both hydrogen and ionic bonds withfibers and fines. Dry strength additives help to increase dry strength,as well as drainage and retention, and are also effective in fixinganions, hydrophobes and sizing agents into fiber products. The forgoingadditives may be added as a percent by weight in the range of 0.5%-10%,and preferably about 1%-6%, and most preferably about 3.5%. In addition,both wet and dry processes may benefit from the addition of wet strengthadditives, for example solutions formulated withpolyamide-epichlorohydrin (PAE) resin such as Kymene 577 or similarcomponent available from Ashland Specialty Chemical Products atashland.com/products. In a preferred embodiment, Kymene 577 may be addedin a percent by volume range of 0.5%-10%, and preferably about 1%-4%,and most preferably about 2% or equal amount with dosing of dry strengthadditives. Kymene 577 is of the class of polycationic materialscontaining an average of two or more amino and/or quaternary ammoniumsalt groups per molecule. Such amino groups tend to protonate in acidicsolutions to produce cationic species. Other examples of polycationicmaterials include polymers derived from the modification withepichlorohydrin of amino containing polyamides such as those preparedfrom the condensation adipic acid and dimethylene triamine, availablecommercially as Hercosett 57 from Hercules and Catalyst 3774 fromCiba-Geigy.

To strengthen the finished yoke, a dry strength additive such as aninorganic salt (e.g., Hercobond 6950 available atsolenis.com/en/industries/tissue-towel/innovations/hercobond-dry-strength-additives/;see also http://www.sfm.state.or.us/CR2K_SubDB/MSDS/HERCOBOND_69 50.PDF)may be employed in the range of 0.5%-10% by weight, and preferably about1.5%-5%, and most preferably about 4%.

As discussed above, the slurry chemistry may be combined with structuralfeatures such as ribs located between the collars to provide enhancedrigidity over time even in wet environments.

While the present invention has been described in the context of theforegoing embodiments, it will be appreciated that the invention is notso limited. For example, the various geometric features and chemistriesmay be adjusted to accommodate additional applications based on theteachings of the present invention.

A method is thus provided for manufacturing a beverage yoke. The methodincludes: forming a wire mesh over a mold comprising a mirror image ofthe yoke including a plurality of collars interconnected by a web;immersing the wire mesh in a fiber-based slurry bath; drawing a vacuumacross the wire mesh to cause fiber particles to accumulate at the wiremesh surface; and removing the wire mesh from the slurry bath; whereinthe slurry comprises a moisture/water barrier component in the range of1.5%-4% by weight.

In an embodiment the slurry comprises a moisture barrier component inthe range of about 4%.

In an embodiment the moisture barrier component comprises alkyl ketenedimer (AKD).

In an embodiment the moisture barrier component comprises alkyl ketenedimer (AKD) 80.

In an embodiment the slurry comprises a fiber base of OCC/NP at a ratioin the range of 0.5/9.5.

In an embodiment the slurry further comprises a dry strength componentin the range of 1%-7% by weight.

In an embodiment the starch component comprises a cationic liquidstarch.

In an embodiment the slurry further comprises a wet strength componentsuch as Kymene (e.g., Kymene 577) in the range of 1%-4% by weight.

In an embodiment the moisture/water barrier comprises AKD in the rangeof about 4%, wherein the AKD may be added to the pulp slurry as adiluted solution (e.g., 1:10 ADK:Water); the slurry comprises a cationicliquid starch component in the range of 1%-7%.

In an embodiment the slurry further comprises a rigidity component inthe range of 1%-5% by weight.

As used herein, the word “exemplary” means “serving as an example,instance, or illustration.” Any implementation described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other implementations, nor is it intended to beconstrued as a model that must be literally duplicated.

While the foregoing detailed description will provide those skilled inthe art with a convenient road map for implementing various embodimentsof the invention, it should be appreciated that the particularembodiments described above are only examples, and are not intended tolimit the scope, applicability, or configuration of the invention in anyway. To the contrary, various changes may be made in the function andarrangement of elements described without departing from the scope ofthe invention.

1. A method of manufacturing a yoke configured to carry beverage cans,comprising: providing a wire mesh mold in the shape of the yoke;immersing the mold in a fiber-based slurry; drawing a vacuum across thewire mold to cause fiber particles to accumulate at the wire meshsurface; and removing the mold and attached fiber particles from theslurry; and subsequently drying the fiber particles to yield the yoke;wherein the slurry comprises a moisture barrier.
 2. The method of claim1, wherein the moisture barrier is in the range of 0.5%-10% by weight.3. The method of claim 2, wherein the moisture barrier comprises alkylketene dimer (AKD).
 4. The method of claim 1, wherein the moisturebarrier comprises alkyl ketene dimer (AKD)
 79. 5. The method of claim 1wherein the slurry comprises a fiber base of about 70% OCC and about30%.
 6. The method of claim 1, wherein the slurry further comprises astrength additive in the range of 1.5%-4% by weight.
 7. The method ofclaim 1, wherein the strength additive comprises Hercobond.
 8. Themethod of claim 1, wherein: the moisture barrier comprises AKD in therange of about 4%; and the slurry comprises OCC and NP.
 9. A slurry foruse in vacuum forming a beverage yoke, comprising: a moisture barriercomprising AKD in the range of about 4% by weight; a fiber basecomprising OCC and NP; and a wet strength resin in the range of about 4%by weight; and a dry strength additive in the range of about 4% byweight.
 10. The slurry of claim 9, wherein the dry strength additivecomprises Hercobond
 6950. 11. The slurry of claim 9, wherein the wetstrength resin comprises kymene 1500LV.
 12. A method of manufacturing acarrier for cylindrically shaped containers, comprising: providing amesh mold in the shape of the carrier; immersing the mold in afiber-based slurry; drawing a vacuum across the mold to cause fiberparticles to accumulate at the mesh surface; and removing the mold andaccumulated fiber particles from the slurry; and subsequently drying thefiber particles to yield the carrier; wherein the slurry comprises: afiber base including at least one of OCC and NP; a moisture barrieradditive in the range of about 4% by weight; a wet strength additive inthe range of about 4% by weight; and a dry strength additive in therange of about 4% by weight.
 13. The method of claim 12, wherein: themoisture barrier additive comprises AKD; the wet strength additivecomprises a polyamidoamine-epichlorohydrin (PAE) resin; and the drystrength additive comprises a cationic modified polyamine water solublepolymer.
 14. The method of claim 12, wherein the carrier comprises aplurality of collars interconnected by a web, wherein each collarexhibits a nominal diameter of about 1.95 inches and the web exhibits asubstantially uniform thickness of about 0.03 inches.